Device and method for quickly identifying a harmful flow pattern in gathering and transportation vertical pipe

Abstract

The invention relates to a device and a method for quickly identifying a harmful flow pattern in a gathering and transportation vertical pipe, which comprises the following steps: 1) fixedly connecting one end above a water surface, of a gathering and transportation vertical pipe to one end of a vertical pipe, and connecting the other end of the vertical pipe to one end of a horizontal pipe through an elbow, and fixedly connecting the other end of the horizontal pipe to a gas-liquid separator; 2) arranging resistance components on the vertical pipe and the horizontal pipe; 3) acquiring a differential pressure signal of the pipe at the two resistance components; 4) calculating a mean value and a standard deviation of the differential pressure signal of the pipeline at the two resistance components; 5) calculating the main frequency of the power spectrum of the differential pressure signal of the pipe at the two resistance components; 6) identifying whether the gathering and transportation vertical pipe is a harmful flow pattern, and proceeding to a step 7) when the gathering and transportation vertical pipe is the harmful flow pattern; and outputting the flow pattern identificationresult of the gathering and transportation vertical pipe when the gathering and transportation vertical pipe is not the harmful flow pattern; 7) and identifying the type of the harmful flow pattern ofthe gathering and transportation vertical pipe. The device and method can be widely applied to multiphase flow detection in the petroleum engineering field.

Description

technical field [0001] The invention relates to a device and method for quickly identifying harmful flow patterns in a gathering riser, and belongs to the field of multiphase flow detection in petroleum engineering. Background technique [0002] In the development of offshore oil and gas, because the subsea gas-liquid separation method is not mature enough, the oil and gas produced on the seabed are usually lifted to the production platform on the sea surface by means of mixed transportation. The pipe section is called the gathering riser. Since a platform usually collects the output of multiple oil wells, there is a certain length of pipe section laid along the seabed from the bottom of the gathering riser to the wellhead. When the gas-liquid flow rate is low, long liquid plugs are easily formed in the gathering standpipe, which flows out alternately with the gas phase, resulting in severe fluctuations in the outlet flow rate. This type of flow pattern is called severe slu...

AI Technical Summary

Problems solved by technology

However, the system requires underwater measurement; for the built platform, the submarine construction technology required for corresponding transformation is difficult and the construction period is relatively long, which has a greater impact on production; the working environment of the underwater sensor itself is also very difficult. It is even worse, and the low temperature environment on the seabed is prone to blockage of the impulse pipe

The prior art also discloses a flow pattern identification method based on the pressure signal at the top of the gathering riser. This method does not require underwater signals and has a small amount of reconstruction work, and is easy to implement on the built platform; It takes a long time to collect pressure signals, and the required signal length is 5 to 15 times that of the aforementioned rapid identification system (related to the number of identified flow types), which cannot achieve rapid identification

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